Charles e



(No Model.)

U. E. SORIBNER.

SUBS'I'ATION APPARATUS FOR TELEPHONE SYSTEMS.

Patented Oct. 18, 1892.

Kiwi

wiZW/QSS 6,3

fiw 7729 re-mum, \ynsumrou, n. c.

UNITED STATES PATENT @Errcn.

CHARLES E. SCRIBNER, OF oHicAe iLLiNois, ASSIGNOR TO THE WESTERN ELECTRIC COMPANY, OF SAME PLACE.

SUB-STATION APPARATUS FOR TELEPHONE SYSTEMS.

SPECIFICATION forming part of Letters Patent No. 484,613, dated October 18, 1892. Application filed January 21, 1892. Serial No. 418,824. (No model.)

To all wTwm it may concern: slowly alternating or pulsating signaling-cur- Be it known that 1, CHARLES E. SORIBNER, rents. I am thus enabled to direct, as it were, acitizen of the United States, residing at O'nicurrent of each specific character through its cago, in the county of Cook and State of Illiappropriate instrument and to prevent its es- 55 nois, have invented a certain new and useful cape through the other instruments without Improvement in Sub-Station Apparatus for opening any of the branch circuits. Thereby Telephone Systems, (Case No. 288,) of which I avoid the inclusion in any branch circuit of the following is a full, clear, concise, and exact contact-points, which are likely to become undescription, reference being had to the accomreliable through corrosion and wear. 60 1o panying drawings, forming a part of this I will describe my invention in greater despecificat'iontail, illustrating the description by the ac- My invention relates to the construction companying drawings. and arrangement of apparatus at sub-stations Of the drawings, Figure 1 is a front elevaof telephone systems. Its object is to avoid tion of a telephone and transmitter and a call- 65 opening the line-circuit or any branch thereof box containing the signaling and other accesat any time at the substation. sory apparatus. Fig. 2 is a diagram showing The apparatus at the sub-station ordinarily the circuits of the apparatus. comprises a magneto-generator for Sending In Fig. 1, a is a magnetogeiierator of ordisignaling-currents, a bell adapted to respond nary constructiomhaving an armature of high 70 to incoming signaling-currents, and the teleresistance and retardation. One end of the phonereceiver and transmitter. armature-wire is connected to the insulated Heretofore the bell, generator, and telepin a and the other to the shaft which terphone have been placed in parallel branch or minates in the point (L The pin a and the derived circuits between the two portions of point a make contact with the springs 19 and 75 the line, the telephone and generator in nor- .5, respectively. The armature is adapted to mally-open parallel branches, that containbe rotated by means of the gear and pinion ing the telephone being adapted to be closed 0 0, the latter having attached to ita crank when required by contact-points operated by projecting to the outside of the box. a suitable switch and that containing the gend is a polarized signal-bell, also of ordinary 8o erator being closed during the operation construction. 6 is a gravity -hook switch thereof by suitable mechanism, the bell beadapted to close the local circuit, including ing of high resistance and retardation in or-' battery, the microphone, and the primary of der that it might not shunt the telephonic the transmitter induction-coil. It consists of current from the telephone. a lever e, pivoted at 6 A spring 6 gives the 85 In my invention the bell, the generator, hook aconstant upward tendency and makes and the telephone are placed in parallel, each contact with the contact-piece 6 when the in a closed branch or bridge connection behook is allowed to rise. A pin or stud c of tween the two sides of the line, the bell and rubber, comes into contact with the spring generator being of high retardation to prewhen the lever is pressed down and lifts the 90 o vent them from shunting the telephonic curend of the spring away from the contact-anrent, and a small condenser being included vil e in the branch with the telephone to prevent the f is a condenser which may be of two-tenths latter from shunting the signaling-currents. or three-tenths niicrofarad capacity. The self-induction of the branches including g is a telephone-transmitter, and his a tele- 5 5 the bell and the generator makes these phone-receiver.

branches practically open to the rapidly-un- The call-box is provided with various binddulat-ing telephonic currents. 'On the other ing-posts adapted to receive the different exhand, the small condenser in the telephone ternal connections to it. The two posts m are branch, while perfectly transmitting theteleadapted to be connected to the lines. The I00 phonic alternating currents of high frequency, posts it are connected to the telephone h,7c k

makes the branch practically open to the to the secondary of the transmitter inductioncoil, 10 k to the battery and to the primary of the induction-coil. Connections extend from binding-postst' to the spring I) and by the post It to the telephone and from postql to one side of bell d. Post 'i' is connected to spring I), to post and to the other side of hell. Post k is connected to one post Z of condenser fand post K to the other side thereof. Post 10 is connected to spring 6 and post It to pivot e of the lever e.

The circuit connections may be more read- 11y traced in Fig 2, in which three parallel branches n a, 0 0, and p p are shown, connecting the two sides mv m of line. One branch at '11 contains the generator at, another 0 0' includes the bell d, and the third 13 p in cludes the telephone h, the condenser f, and the secondary 'r of the induction-coil of the transmitter g. The primary 3 of this coil is in circuit with the microphone 25 and battery to. The circuit is open at the points e 8 while the telephone is on the book, but is antomatically closed when the telephone is removed from the hook for use.

\Vhen the generator at is operated, a small part of its current is shunted through the bell 01, operating it, and thus indicating to the subscriber that his apparatus is working properly. The remainder of the current passes out on lines m m. When current comes in on the lines m m, a large part of it traverses the bell (l, a little escaping through the high-resistance generator (1 In neither of thesecases does any considerable current traverse the branch 12 19, containing the telephone, on account of the smallness of capac- 1ty of the condenser f. When, however, telephonic current comes over lines m m, substantially the whole of this current traverses the branch 19 19', since the condenser f is practically a perfect transmitter of its undulations and the generator at and the magnets of bell d-are practically opaque to currents having undulations of such high frequency.

It is not essential that the generator (1 be always in circuit. If it be desired, the generator may be in a normally-open branch circuit and may be provided with the well-known mechanism for closing the circuit continuously during the operation of the generator, this mechanism not being open to the usual objection to contact-points to the same extent, since the contact-surfaces are large and are constantly cleaned during use.

Obviously my invention is not limited to use with alternating currents, such as ordinarily employed, but is adapted for use with pulsating or continuous currents, since these also will fail to pass the condenser, although traversing the bell-coils readily.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. The combination, with a line extending to a sub-station, of signal-receivin g apparatus and a telephone at the sub-station, said signal-receiving apparatus and said telephone being in permanently-closed independent parallel branches between the two sides of said line, substantially as described.

2. The combination, with a telephone-line extending to a sub-station, of a telephone and a signal-receiving device in separate permanently-closed parallel branches between the two sides of said line, said signal-receiving device being of high retardation, substantially as described.

3. In combination with a telephone-line extending to a sub-station, a telephone and a signal-receiving device in separate parallel permanently-closed branches between said line, said signal-receiving device being of high retardation, and a condenser included in the branch containing the telephone, substantially as described.

4. The combination, with a telephone-line extending to a sub-station, of a signal-receiving device and a signal-sending device, both of high resistance and retardation, and a telephone in separate permanently-closed parallel branches between the two sides of said line, and a condenser in that branch including the telephone, substantially as described.

5. The combination, with a telephone-line extending to a sub-station, of a signal-sending and a signal-receiving device, both of high resistance and retardation, in two permanently-closed parallel branches between the two sides of said telephone-line, and a telephone, the secondary of a transmitter induction-coil, and a condenser in a third parallel permanently-closed branch between the two sides of said line, substantially as described.

6. The combination, with line-wires, of a signal-receiving device adaptedto receive undulatory or alternating currents .of comparatively low frequency and a receiving device adapted to receive or respond to telephonic ornndulatory currents of high frequency in separate parallel branch circuits between said line-wires, said slow pulsation-receiver being of high retardation, and a condenser in circuit with said telephonic receiver, whereby pulsating currents of low frequency and telephonic currents upon the'line are directed each through its appropriate receiving device and prevented each from traversing the receiving device adapted to the other, substantially as described.

In witness whereof I hereunto subscribe my name this 9th day of Januar A. D. 1892.

CHARLES E. SCRIBNER.

Witnesses:

FRANK R. MCBERTY, GEORGE L. CRAGG. 

